One square foot, to be precise, in the place known as "Hawaii 2," which the horrible people at Cards Against Humanity actually purchased—and then gave away—as part of this year's Holiday Bullshit shenanigans.
Here's where my real estate is located:
Maybe I'll visit it someday. Maybe not. Seems like a lot of trouble.
There was also a large-scale, online puzzle hunt associated with this year's CAH promotion, which ended at a safe hidden on the island. Read all about it on Boing Boing, Max Temkin's blog, or ARGNet, and see the Reddit community writeup of how the puzzles worked.